Trench fever, known also as "five-day fever," was first recognized as a distinct disease in 1916 in European troops engaged in trench warfare. More than 200,000 cases were reported in British troops alone. The disease surfaced again in its last epidemic in troops stationed in Europe during World War II. Relatively very few cases have been documented in the world since then. In contrast to epidemic typhus fever and epidemic relapsing fever, trench fever rarely causes death, but severe cases can be debilitating.

Causative agent

A rod-shaped bacterium with the scientific name Bartonella quintana.

Geographical distribution of cases

Temperate regions and high elevations in the tropics, including South America.

Symptoms of infection

Non-specific, including headache, muscle ache, fever, and nausea.

Reservoir of Bartonella quintana

Humans are the only known reservoir.

Vectors of Bartonella quintana

The human body louse Pediculus humanus.

Mode of transmission

Via feces of infected body lice being scratched into the skin.

NOTE: Bacteria remain infective in dried feces of body lice for months, and they can be inhaled.

Diagnosis of infection

Symptoms together with infestation by human body lice.

Laboratory tests that detect antibodies to Bartonella quintana in a patient's blood.